Combination indicating calipers



COMBINATION INDIGATING CALIPERS Filed Nov. 16, 1945 Patented Feb. 19, 1946 UNITED STATES PATENT OFFICE 2,395,154 COMINTION INDICATING CALIPERS Ivar V. Thulin, Upper Darby, Pa.

Application November 16, 1943, Serial No. 510,564 6 claims. (o1. :a3-14s) Another object of the present invention is to provide an exceedingly simple and effective tool for accurately indicating a variance in size relative to a predetermined wanted size measured by the tool.

Another object of the invention is to construct outside calipers which can be used on work in motion, without the possibility of said calipers sticking on the work and damaging either said work or the calipers, or injuring the worker, to obtain a measurement of the variance between the setting of the calipers and the test measurement taken.

A further object of the invention is to providev inside calipers that may be adjusted or set to a predetermined or desired inside measurement and then other measurements of less dimensions taken which will indicate the difference between the two measurements without effecting the setting of the calipers, except temporarily.

With the above and other objects in view this invention consists of the details of construction and combination of elements hereinafter set forth and then designated by the claims.

In order that those skilled in the art to which this invention appertains may understand how to make and use the same I will describe its construction in detail referring by numerals to the accompanying drawing forming a part hereof,V in which: Y

Fig. 1 is a side elevation of the outside calipers illustrating them in a set position to a predetermined measurement and showing in dotted lines the position oi the pointer after a test or secondary measurement has been taken.

Fig. 2 is a similar View of the same calipers illustrating the positions of the several elements as a test measurement is taken.

Fig. 3 is an enlarged fragmentary edge view thereof.

Fig. 4 isa section on the line 4--4 of Fig. 1.

Fig. 5 is a side elevation of the inside calipers 55 pers including a legI I constructed as an integralV unit with a curved lower end terminating in a toe I2. The companion leg I3 comprises two sections I4 and I5, the upper section I4 being of the same general shape as the major portion ofthe leg II but ending short thereof, as at I6, while the lower section includes the curved portion terminating in the toe I'I and a shank I8 having a nose I9 projecting from the inner edge thereof at the top end.

The lower section I5 is pivcted intermediate its ends, as at 20, to the lower end of the upper section I4 and the curved portion of said lower section I5 is in line with said upper section I4 but the shank portion I8 of said lower section I5 is offset laterally relative to the curved portion, Fig. 3, so as to be imposed upon a face of the upper section I4.

The two legs II and I3 are hinged or fulcrumedl on the joint element 2| and their lower or toe ends are urged apart by a spring ring 22 which is a common construction in calipers. The spread of saidlegs is regulated by an adjusting mechanism which, for purposes of illustration, is shown as a screw or threaded rod 23 having an end fixed to a post 24 pivoted to the leg I I and loosely projecting through a post 25 pivoted to the upper section I4 of the other leg I3 and having an adjusting nut 26 mounted on said threaded rod and engaging the post 25.

The lower section I5 of the two-piece leg I3 is held under tension to urge the toe I1 towards the toe I2 by a spring 21 which, for purposes of illustration, is shown as of the coil type having'one end mounted on a hook shaped pin 28 carried by and projecting from the inner edge of the upper section I4. The other end of said spring bears against an edge of the shank I3 of the lower section I5 and is held in position by a pin 29 projecting from the shank edge.

The nose I9 engages or merely contacts the rounded heel 30 of a pointer 3| pivoted at 32 to the upper section I4 of the leg I3. The pivot is above the point of contact of the nose with the pointer heel and said pivot is held under resilient tension by a flat spring 33, Fig. 3, through which said pivot passes and said spring engages the face of the leg I3 opposite the one on which the pointer is mounted. Portions of the spring 33, such as ngers 34 bent up out of the spring material at opposite ends, engage an edge of the leg I3 to prevent shifting of said spring. This produces suillcient friction between the pivot, pointer and leg to hold said pointer at any set position under al1 ordinary circumstances.

The pointer 3| coacts with graduations 35 on a dial 36 carried by and projecting from the outer edge of the upper section I4 of the leg I3 and said dial has a stop 31 thereon to limit the movements of the lower section I5 of said leg I3 as said lower section is actuated by a spring 21. The graduations may represent any preselected degrees of measurement according to the spaces between them and all or certain ones of them may be numbered to assist the operator in quickly ascertaining the measurement indicated.

In practice, the calipers may be iirst set to a measurement desired, as shown in Fig. 1, by properly manipulating the adjusting apparatus consisting, primarily, of the threaded rod 23 and nut 26 and using a rule, micrometers, gauge or a iinished piece of work, until the toes I2 and I1 are the desired distance apart. During the adjustment the operator must make sure that the lower leg section I5 does not move against the action of the spring 21.

Assume a piece of work on a lathe is being turned down to a given diameter represented by the setting of the calipers as shown in Fig. l. Without stopping the machine, the calipers may be caused to straddle the work by merely pushing the legs over the work. As soon as this has been done the calipers may be immediately withdrawn. So long as the Work being calipered is larger than the nished product desired, the lower section I5 of the leg i3 will be moved to some new position, as suggested by the showing in Fig. 2. This Will cause the nose I9 to move the pointer 3i which will indicate on the graduations 35 the variation between the desired or wanted size and the oversize part of the work measured. As the calipers are Withdrawn from the work piece, the spring 21 will return the lower leg section I5 to its former position, being arrested` by the stop 31, but

the pointer 3l will remain in the indicating po.

sition as suggested by the dotted line location in Fig. 1. The operator may now read the measurement obtained and set his machine for an additional cut or cuts. Before taking another test measurement the pointer should be returned to its neutral or zero position by manually forcing said pointer back until the hee1 35 again engages the nose I9. From the foregoing it will be apparent that when the calipers are removed from the work the measurement reading will be preserved until the pointer is reset, even though the caliper legs return to their former spacing.

A secondary result accrues from the structure in that the calipers cannot firmly grip the Work, because of the resilient mounting of the lower leg section, therefore said calipers will not be pulled from the hand of the operator and the possibility of damage to the calipers or the machine, or injury to the operator is eliminated.

The inside calipers d5, Figs. 5 and 6, are practically the same as the outside calipers except that the dial and associated parts are on the inside of a leg instead of the outside so as not to be in the way when measurements are being taken. Said inside calipers includes, a leg 4I constructed as an integral unit with an outwardly curved lower end terminating in a toe 42. The

companion leg 43 comprises two sections 44 and 45, the upper section being straight like the other leg, but ending short of the latter, as at 46, while the lower section includes the outwardly curved portion terminating in the toe 41 and a shank 48 having a nose 49 projecting from the outer edge thereof at the top end.

The lower section 45 is pivoted intermediate its ends, as at 50, to the lower end of the upper section 44 and the curved portion of said lower section 45 is in line with said upper section 44 but the shank portion 43 of said lower section 45 is offset laterally relative to the toe portion so as to be imposed upon a face of the upper section 44.

The two legs 4I and 43 are fulcrumed on the joint element 5I and their toe ends are urged apart by a spring ring 52. The spread of said legs is regulated by an adjusting mechanism consisting of a threaded rod 53 having an end iixed to a post 54 pivoted to the leg 4I and loosely projecting through a post 55 pivoted to the upper leg section 44 of the leg 43 and having an adjusting nut 5G mounted on said threaded rod and engaging the post 55.

The lower section 45 of the two-piece leg 43 is held under tension to urge the toe 41 towards the toe 42 by a spring 51 which is shown as of thc coil type having one end mounted on a hook shaped pin 58 carried by and projecting from the outer edge of the upper section 44. The other end of said spring bears against an edge of the shank 48 of the lower section 45 and is held in position by a pin 59 projecting from the shank edge.

The nose 55 engages or merely contacts the rounded heel 65 of a pointer 6I pivoted at 62 to the upper section 44 of the leg 43. The pivot is above the point of contact of the nose with the pointer heel and said pivot is held under resilient tension in the same manner as described in connection with the outside calipers.

The pointer coacts with graduations 53 on a dial 64 carried by and projecting from the inner edge of the upper section 44 of the leg 43 and said dial has a stop 65 thereon to limit the movements of the lower leg section 45 as the latter is actuated by the spring 51. The graduations mayv be numbered and represent any preselected degrees of measurement according to the spaces between them.

In using the inside calipers, it will be assumed that a hole is to be formed in a piece of work 66 to the size indicated by the dotted lines 61 in Fig. 6 which is the same size as the space indicated by the broken arrows 58, Fig. 5. The hole might be bored undersize and thereafter reamed to the finished size and for this reason several test measurements might be necessary.

The calipers are first set to a desired or preselected measurement, a-s shown in Fig. 5, by properly manipulating the adjusting apparatus. To make a test measurement the caliper legs are pressed toward each other and the toe ends inserted in the hole 69. Upon release of the caliper legs they will spread until the toes engage the Walls of the piece of work, as in Fig. 6. The pressing of the legs towards each other may have moved the pointer GI a greater distance than necessary so that while the toes are in engagement with the walls of the piece of Work said pointer is moved back until the heel 55 of said pointer engages the nose 49 thus indicating the proper measurement of any variance between the desired size and the size of the hole at the time of making the test. After the test measurement has been made the calipers may be withdrawn and the pointer will remainin the indicating position until another measurement is to be made.

Of course I do not wish to be limited to the exact details of construction herein shown and described as these may be varied within the scope of the appended claims without departing from the spirit of my invention.

Having described my invention what I claim as new and useful is:

1. Combination indicating calipers comprising a one-piece leg, a two-piece leg, said legs being hingedly connected together, said two-piece leg including an upper section and a lower section pivoted intermediate its ends to the bottom end of the upper section, a pointer pivoted to said upper leg section and having a heel portion with the pivot above the top end of the lower leg section which top end contacts one side of the heel of said pointer, said pointer being frctionally held by its pivot so as to remain in any position, means to urge the top end of said lower leg section away from the pointer, and a scale having graduations with which the pointer coacts.

2. The structure in claim l wherein said friction is provided by resilient means acting upon the pointer.

3. Combination indicating calipers comprising a one-piece leg and a two-piece leg hinged at their upper ends, means to urge their lower ends apart. means to set them at any desired adjustment, said two-piece leg including an upper section and a lower `section pivoted intermediate its end to the bottom end of the upper section so that said lower section consists of a toe end and a shank, and a pointer pivoted to the upper leg section above the shank of the lower leg section and including a heel portion having' one side thereof in the path of travel of the top end of said shank, said pointer being frictionally held by its pivot so as to remain in any position.

4. The structure in claim 3 wherein the pointer heel portion which is contacted by the lower leg section is rounded convexly and the shank of the lower leg section has a nose projecting from the edge thereof at the top end to engage one side of the pointer heel portion.

5. In a pair of combination indicating calipers, a two piece leg consisting of an upper section, a lower section comprising a toe end and a shank, said shank offset laterally a distance approximating the thickness of the upper leg section and on which said shank is imposed with the toe end in the same plane as the upper leg section, means to pivot said lower section intermediate its ends to an end oi the upper leg section, a pointer, and means to pivot said pointer intermediate its ends with the pivot point above the top end of the shank, the part of the pointer below the pivot point constituting a heel portion in the path of travel of said top end of the shank, said pointer being frictionally held by its pivot so as to remain in any position.

6. The structure in claim 5, in combination with means to urge the top end of the shank away from the pointer.

IVAR V. THULIN. 

